Sex hormones in the modulation of irritable bowel syndrome

Compelling evidence indicates sex and gender differences in epidemiology,symptomatology,pathophysiology,and treatment outcome in irritable bowel syndrome(IBS).Based on the female predominance as well as the correlation between IBS symptoms and hormonal status,several models have been proposed to examine the role of sex hormones in gastrointestinal(GI)function including differences in GI symptoms expression in distinct phases of the menstrual cycle,in pre-and post-menopausal women,during pregnancy,hormonal treatment or after oophorectomy.Sex hormones may influence peripheral and central regulatory mechanisms of the brain-gut axis involved in the pathophysiology of IBS contributing to the alterations in visceral sensitivity,motility,intestinal barrier function,and immune activation of intestinal mucosa.Sex differences in stress response of the hypothalamic-pituitary-adrenal axis and autonomic nervous system,neuroimmune interac-tions triggered by stress,as well as estrogen interactions with serotonin and corticotropin-releasing factor signaling systems are being increasingly recognized.A concept ofmicrogenderomerelated to the potential role of sex hormone modulation of the gut microbiota is also emerging.Significant differences between IBS female and male patients regarding symptomatology and comorbidity with other chronic pain syndromes and psychiatric disorders,together with differences in efficacy of serotonergic medications in IBS patients confirm the necessity for more sex-tailored therapeutic approach in this disorder.     

Cognitive behavioral approach to understanding irritable bowel syndrome

Irritable bowel syndrome(IBS)is considered a biopsychosocial disorder,whose onset and precipitation are a consequence of interaction among multiple factors which include motility disturbances,abnormalities of gastrointestinal sensation,gut inflammation and infection,altered processing of afferent sensory information,psychological distress,and affective disturbances.Several models have been proposed in order to describe and explain IBS,each of them focusing on specific aspects or mechanisms of the disorder.This review attempts to present and discuss different determinants of IBS and its symptoms,from a cognitive behavioral therapy framework,distinguishing between the developmental predispositions and precipitants of the disorder,and its perpetuating cognitive,behavioral,affective and physiological factors.The main focus in understanding IBS will be placed on the numerouspsychosocial factors,such as personality traits,early experiences,affective disturbances,altered attention and cognitions,avoidance behavior,stress,coping and social support.In conclusion,a symptom perpetuation model is proposed.     

Personality traits and emotional patterns in irritable bowel syndrome

The review focuses on those personality traits(neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness), constructs(alexithymia and distressed- Type D personality) and emotional patterns(negative and positive) that are of particular concern in health psychology, with the aim to highlight their potential role on the pathogenesis, onset, symptom clusters, clinical course, and outcome of irritable bowel syndrome(IBS). Personality traits and emotional patterns play key roles in affecting autonomic, immune, inflammatory, and endocrine functions, thus contributing not only to IBS clinical expression and symptomatic burden, but also to disease physiopathology. In this sense, psychological treatments should address those personality traits and emotional features that are constitutive of, and integral to IBS. The biopsychosocial model of illness applied to IBS acknowledges the interaction between biological, psychological, environmental, and social factors in relation to pain and functional disability. A holistic approach to IBS should take into account the heterogeneous nature of the disorder, and differentiate treatments for different types of IBS, also considering the marked individual differences in prevalent personality traits and emotional patterns. Beyond medications, and lifestyle/dietary interventions, psychological and educational treatments may provide the optimal chance of addressing clinical symptoms, comorbid conditions, and quality of life in IBS patients.     

Intestinal microbiota in pathophysiology and management of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a functional bowel disorder without any structural or metabolic abnormalities that sufficiently explain the symptoms, which include abdominal pain and discomfort, and bowel habit changes such as diarrhea and constipation. Its pathogenesis is multifactorial: visceral hypersensitivity, dysmotility, psychosocial factors, genetic or environmental factors, dysregulation of the brain-gut axis, and altered intestinal microbiota have all been proposed as possible causes. The human intestinal microbiota are composed of more than 1000 different bacterial species and 10¹⁴ cells, and are essential for the development, function, and homeostasis of the intestine, and for individual health. The putative mechanisms that explain the role of microbiota in the development of IBS include altered composition or metabolic activity of the microbiota, mucosal immune activation and inflammation, increased intestinal permeability and impaired mucosal barrier function, sensory-motor disturbances provoked by the microbiota, and a disturbed gut-microbiota-brain axis. Therefore, modulation of the intestinal microbiota through dietary changes, and use of antibiotics, probiotics, and anti-inflammatory agents has been suggested as strategies for managing IBS symptoms. This review summarizes and discusses the accumulating evidence that intestinal microbiota play a role in the pathophysiology and management of IBS.     

Probiotics and irritable bowel syndrome

Irritable bowel syndrome(IBS)is common gastrointestinal problems.It is characterized by abdominal pain or discomfort,and is associated with changes in stool frequency and/or consistency.The etiopathogenesis of IBS may be multifactorial,as is the pathophysiology,which is attributed to alterations in gastrointestinal motility,visceral hypersensitivity,intestinal microbiota,gut epithelium and immune function,dysfunction of the brain-gut axis or certain psychosocial factors.Current therapeutic strategies are often unsatisfactory.There is now increasing evidence linking alterations in the gastrointestinal microbiota and IBS.Probiotics are living organisms which,when ingested in certain numbers,exert health benefits beyond inherent basic nutrition.Probiotics have numerous positive effects in the gastrointestinal tract.Recently,many studies have suggested that probiotics are effective in the treatment of IBS.The mechanisms of probiotics in IBS are very complex.The purpose of this review is to summarize the evidence and mechanisms for the use of probiotics in the treatment of IBS.     

Neuroimaging the brain-gut axis in patients with irritable bowel syndrome

AIM:To summarize and synthesize current literature on neuroimaging the brain-gut axis in patients with irritable bowel syndrome(IBS).METHODS:A database search for relevant literature was conducted using Pub Med,Scopus and Embase in February 2015.Date filters were applied from the year2009 and onward,and studies were limited to those written in the English language and those performed upon human subjects.The initial search yielded 797articles,out of which 38 were pulled for full text review and 27 were included for study analysis.Investigations were reviewed to determine study design,methodology and results,and data points were placed in tabular format to facilitate analysis of study findings across disparate investigations.RESULTS:Analysis of study data resulted in the abstraction of four key themes:Neurohormonal differences,anatomic measurements of brain structure and connectivity,differences in functional responsiveness of the brain during rectal distention,and confounding/correlating patient factors.Studies in this review noted alterations of glutamate in the left hippocampus(HIPP),commonalities across IBS subjects in terms of brain oscillation patterns,cortical thickness/gray matter volume differences,and neuroanatomical regions withincreased activation in patients with IBS:Anterio cingulate cortex,mid cingulate cortex,amygdala anterior insula,posterior insula and prefrontal cortex.A striking finding among interventions was the substantia influence that patient variables(e.g.,sex,psychologica and disease related factors)had upon the identification of neuroanatomical differences in structure and con nectivity.CONCLUSION:The field of neuroimaging can provide insight into underlying physiological differences that distinguish patients with IBS from a healthy population.     

Role of environmental pollution in irritable bowel syndrome

Irritable bowel syndrome (IBS), with the prevalence of 10%-20 % of the population has become an emerging problem worldwide. IBS is a functional gastrointestinal (GI) disorder characterized by abdominal pain or discomfort and altered bowel habits. The etiology of IBS contains genetic, psychological, and immunological factors, and has not been fully elucidated; of note, recent studies also point at environmental pollution and its role in the development of functional GI diseases. In this review we focus on several environmental factors, such as bacterial contamination, air pollution, radiation and even stress as potential triggers of IBS. We discuss associated disturbances in homeostasis, such as changes in intestinal microbiome and related pathophysiological mechanisms. Based on the effect of environmental factors on the GI tract, we also propose novel targets in IBS treatment.     

Anger and ego-defence mechanisms in non-psychiatric patients with irritable bowel syndrome

BACKGROUND: Irritable bowel syndrome is commonly accepted as a disorder closely influenced by affective factors, which can either trigger the symptoms or contribute to their persistence, independently from their aetiology. It has been previously documented that irritable bowel syndrome patients respond to a variety of emotional states (anger, fear and anxiety) with an increase in colonic motility. AIMS: The aim of this study was to evaluate the experience and the expression of anger and the prevalent ego-defence mechanisms in a group of non-psychiatric patients with irritable bowel syndrome. SUBJECTS: Fifty-two patients with irritable bowel syndrome (18 males, 34 females) and 100 healthy volunteers from the community (44 males, 56 females) matched for age, level of education and social-status were enrolled. METHODS: Assessment was conducted using the State-Trait Anger Expression Inventory and the Defence Mechanism Inventory. RESULTS: No important differences between the two examined groups were found using the State-Trait Anger Expression Inventory and Defence Mechanism Inventory. CONCLUSIONS: It can be hypothesised that stable personality features and habits, such as anger disposition and defence mechanisms, play only a marginal role in irritable bowel syndrome, while psychological and psychosocial influences may act as predisposing or precipitating factors which contribute to the pathogenesis or expression of irritable bowel symptoms.     

精神心理因素在肠易激综合征发病中的作用及性别差异研究

目的本研究通过比较肠易激综合征(IBS)患者与健康人以及男、女IBS患者之间在焦虑、抑郁等方面的差异,探讨精神心理因素在IBS发病中的作用以及性别差异。方法采用焦虑自评量表(SAS),抑郁自评量表(SDS)对50例IBS患者及50例健康人进行评分。结果IBS患者组焦虑、抑郁评分显著高于健康人组(53.31±13.77vs41.14±7.92;51.95±13.87vs42.29±8.15,P<0.001),而男性和女性IBS患者焦虑、抑郁评分没有显著性差异(51.88±13.92vs54.73±12.61;51.34±14.07vs52.56±13.69,P>0.05)。结论焦虑、抑郁在lBS患者中比健康人更多见,在IBS发病中起重要作用;男性和女性IBS患者在精神心理因素方面没有显著性差异。     

5-羟色胺转运体表达与肠易激综合征躯体及心理症状的相关性

目的 研究5-羟色胺转运体(SERT) mRNA及蛋白表达水平与肠易激综合征(IBS)患者躯体和心理症状的相关性.方法 选取消化科门诊IBS患者254例为病例组,健康体检者及志愿者120名为对照组.采用实时定量PCR检测SERT mRNA,Western印迹分析检测SERT的蛋白表达量,应用精神心理症状自评量表(SCL-90)评测研究对象,探讨SERT蛋白表达与心理症状之间的相关性.结果 便秘型肠易激综合征(C-IBS)95例,腹泻型肠易激综合征(D-IBS)116例,交替型肠易激综合征(A-IBS)43例.C-IBS组SERT mRNA及蛋白表达(0.58±0.24;0.99±0.51)显著高于A-IBS组(0.37±0.22;0.67±0.34)、D-IBS组(0.41±0.26;0.71±0.41)和对照组(0.42±0.29;0.78±0.47)(均数差异=0.21、0.17、0.16,均P＜0.01;均数差异=0.31、0.27、0.21,均P＜0.05),A-IBS组与D-IBS组间比较差异无统计学意义(P＞0.05).SERT蛋白表达量与躯体化症状(r=-0.67,P＜0.01)、抑郁因子(r=-0.81,P＜0.01)、焦虑因子(r=-0.72,P＜0.01)和敌对因子呈负相关(r=-0.66,P＜0.01),与人际关系敏感、强迫症状、恐惧、偏执和精神病因子均不存在相关性(P＞0.05).结论 结肠黏膜SERT mRNA及蛋白的水平与IBS患者的躯体及心理症状相关,患者SERT mRNA及蛋白表达越多越容易出现便秘症状,而SERT蛋白含量越少越容易出现躯体化、焦虑、抑郁和敌对的情绪表现.     

肠易激综合征患者心理评价

目的　比较肠易激综合征 (IBS)患者和健康人在个性、焦虑、抑郁、生活事件等方面的差别 ,以揭示个性、焦虑、抑郁、生活事件与IBS的关系。方法　采用龚氏修订的艾森克个性问卷 (成人版 )、宗氏抑郁自评量表、焦虑自评量表及生活事件量表对 89例IBS患者及 73例健康人进行评分。结果　IBS患者内外向分值显著低于健康人 (5 0 .47± 11.63∶5 8.40± 9.87,P <0 .0 0 1) ,而神经质、抑郁、焦虑、负性生活事件分值分别显著高于健康人 (分别为 5 6.85± 13 .2 6∶48.78± 13 .45 ;5 2 .75± 14 .70∶41.2 0± 7.68;5 3 .0 4±15 .5 9∶41.42± 8.90 ;5 2 .71± 5 9.81∶3 5 .2 2± 3 1.42 ,P <0 .0 5 )。结论　内倾和神经质个性、焦虑、抑郁及负性生活事件与肠易激综合征密切相关     

Personality factors and profiles in variants of irritable bowel syndrome

AIM: To study the association between irritable bowel syndrome (IBS) variants (constipation,diarrhea,or both) and personality traits in non-psychiatric patients. METHODS: IBS was diagnosed using the Rome Ⅱ diagnostic criteria after exclusion of organic bowel pathology. The entry of each patient was confirmed following a psychiatric interview. Personality traits and the score of each factor were evaluated using the NEO Five Factor Inventory. RESULTS: One hundred and fifty patients were studied. The mean age (± SD) was 33.4 (± 11.0) year (62% female). Subjects scored higher in neuroticism (26.25 ± 7.80 vs 22.92 ± 9.54,P < 0.0005),openness (26.25 ± 5.22 vs 27.94 ± 4.87,P < 0.0005) and conscientiousness (32.90 ± 7.80 vs 31.62 ± 5.64,P < 0.01) compared to our general population derived from universities of Iran. Our studied population consisted of 71 patients with Diarrhea dominant-IBS,33 with Constipation dominant-IBS and 46 with Altering type-IBS. Scores of conscientiousness and neuroticism were significantly higher in C-IBS compared to D-IBS and A-IBS (35.79 ± 5.65 vs 31.95 ± 6.80,P = 0.035 and 31.97 ± 9.87,P = 0.043,respectively). Conscientiousness was the highest dimension of personality in each of the variants. Patients with C-IBS had almost similar personality profiles,composed of higher scores for neuroticism and conscientiousness,with low levels of agreeableness,openness and extraversion that were close to those of the general population. CONCLUSION: Differences were observed between IBS patients and the general population,as well as between IBS subtypes,in terms of personality factors. Patients with constipation-predominant IBS showed similar personality profiles. Patients with each subtype of IBS may benefit from psychological interventions,which can be focused considering the characteristics of each subtype.     

Recent advances in pharmacological treatment of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a highly prevalent functional disorder that reduces patients’ quality of life. It is a chronic disorder characterized by abdominal pain or discomfort associated with disordered defecation in the absence of identifiable structural or biochemical abnormalities. IBS imposes a significant economic burden to the healthcare system. Alteration in neurohumoral mechanisms and psychological factors, bacterial overgrowth, genetic factors, gut motility, visceral hypersensitivity, and immune system factors are currently believed to influence the pathogenesis of IBS. It is possible that there is an interaction of one or more of these etiologic factors leading to heterogeneous symptoms of IBS. IBS treatment is predicated upon the patient’s most bothersome symptoms. Despite the wide range of medications and the high prevalence of the disease, to date no completely effective remedy is available. This article reviews the literature from January 2008 to July 2013 on the subject of IBS peripherally acting pharmacological treatment. Drugs are categorized according to their administration for IBS-C, IBS-D or abdominal pain predominant IBS.     

Gut dysbiosis and irritable bowel syndrome: The potential role of probiotics

Objective

To discuss the role of gut dysbiosis in the development of irritable bowel syndrome (IBS) and the impact of probiotics as a potential therapeutic measure.

褪黑激素与肠易激综合征

肠易激综合征是一种原因不明的慢性肠功能紊乱性疾病，其发病机制尚不清楚。其治疗方法也在不断改进中，褪黑激素对肠易激综合征的治疗有着积极的作用。     

Immunomodulation of enteric neural function in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder which is characterised by symptoms such as bloating, altered bowel habit and visceral pain. It’s generally accepted that miscommunication between the brain and gut underlies the changes in motility, absorpto-secretory function and pain sensitivity associated with IBS. However, partly due to the lack of disease-defining biomarkers, understanding the aetiology of this complex and multifactorial disease remains elusive. Anecdotally, IBS patients have noted that periods of stress can result in symptom flares and many patients exhibit co-morbid stress-related mood disorders such as anxiety and depression. However, in addition to psychosocial stressors, infection-related stress has also been linked with the initiation, persistence and severity of symptom flares. Indeed, prior gastrointestinal infection is one of the strongest predictors of developing IBS. Despite a lack of overt morphological inflammation, the importance of immune factors in the pathophysiology of IBS is gaining acceptance. Subtle changes in the numbers of mucosal immune cell infiltrates and elevated levels of circulating pro-inflammatory cytokines have been reproducibly demonstrated in IBS populations. Moreover, these immune mediators directly affect neural signalling. An exciting new area of research is the role of luminal microbiota in the modulation of neuro-immune signalling, resulting in local changes in gastrointestinal function and alterations in central neural functioning. Progress in this area has begun to unravel some of the complexities of neuroimmune and neuroendocrine interactions and how these molecular exchanges contribute to GI dysfunction     

Traditional thoughts on the pathophysiology of irritable bowel syndrome

The pathogenesis of symptoms in irritable bowel syndrome (IBS) is multifactorial and varies from patient to patient. Disturbances of motor function in the small intestine and colon and smooth-muscle dysfunction in other gut and extraintestinal regions are prominent. Abnormalities of sensory function in visceral and somatic structures are detected in most patients with IBS, which may relate to peripheral sensitization or altered central nervous system processing of afferent information. Contributions from psychosocial disturbances are observed in patients from tertiary centers and primary practice. Proof of causation of symptom genesis for most of these factors is limited.     

Global research trends in the microbiome related to irritable bowel syndrome: A bibliometric and visualized study

BACKGROUNDIrritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. Dysregulation of the gut–brain axis plays a central role in the pathophysiology of IBS. It is increasingly clear that the microbiome plays a key role in the development and normal functioning of the gut–brain axis.AIMTo facilitate the identification of specific areas of focus that may be of relevance to future research. This study represents a bibliometric analysis of the literature pertaining to the microbiome in IBS to understand the development of this field. METHODSThe data used in our bibliometric analysis were retrieved from the Scopus database. The terms related to IBS and microbiome were searched in titles or abstracts within the period of 2000–2019. VOSviewer software was used for data visualization. RESULTSA total of 13055 documents related to IBS were retrieved at the global level. There were 1872 scientific publications focused on the microbiome in IBS. There was a strong positive correlation between publication productivity related to IBS in all fields and productivity related to the microbiome in IBS (r = 0.951, P < 0.001). The United States was the most prolific country with 449 (24%) publications, followed by the United Kingdom (n = 176, 9.4%), China (n = 154, 8.2%), and Italy (n = 151, 8.1%). The h-index for all retrieved publications related to the microbiome in IBS was 138. The hot topics were stratified into four clusters: (1) The gut–brain axis related to IBS; (2) Clinical trials related to IBS and the microbiome; (3) Drug-mediated manipulation of the gut microbiome; and (4) The role of the altered composition of intestinal microbiota in IBS prevention. CONCLUSIONThis is the first study to evaluate and quantify global research productivity pertaining to the microbiome in IBS. The number of publications regarding the gut microbiota in IBS has continuously grown since 2013. This finding suggests that the future outlook for interventions targeting the gut microbiota in IBS remains promising.     

粪菌移植对肠易激综合征临床疗效和肠道菌群影响的非对照初步研究

目的:探讨粪菌移植治疗IBS的有效性、安全性及其对IBS患者肠道菌群的影响。方法:选择2016年9月至2017年8月在广州市第一人民医院行粪菌移植的IBS住院患者28例。所有IBS患者于粪菌移植前、粪菌移植后4和12周完成肠易激综合征生活质量量表(IBS-QOL)、肠易激综合征严重程度系统评分(IBS-SSS)和胃肠道...